Background
Artificial knee arthroplasty is an effective clinical treatment for knee joint injuries caused by trauma or disease. The artificial knee joint system consists of a femoral condyle prosthesis, a tibia liner and a tibia platform support. As a biological material applied to the artificial knee joint prosthesis, the artificial knee joint prosthesis not only has good repairing effect, relieves the pain of patients and restores the function of the knee joint, but also can not adversely affect tissues around the knee joint of a human body.
Common knee prostheses consist of a metal femoral condyle prosthesis, a polyethylene tibial insert, and a metal tibial plateau. The femoral condyle prosthesis and the tibial insert form a pair of friction pairs. The type of artificial knee joint used clinically at present is a metal femoral condyle prosthesis and a high polymer tibia pad pair. In the long-term friction and abrasion process, toxic metal ions are separated out, a certain concentration is accumulated in a human body to cause chronic diseases, and abrasion fragments can induce bone tissues around the prosthesis to generate bone dissolution; the friction pair formed by the friction pair ensures that the wear rate of the high polymer tibia gasket is very high, the most commonly used high polymer material is ultra-high molecular weight polyethylene, the annual wear amount of the ultra-high molecular weight polyethylene is about 0.1-0.2mm, and the thickness of the high polymer lining can be continuously reduced in the long-term friction process, so that the strength of the tibia gasket is influenced. In addition, there is another type of artificial knee prosthesis: the ceramic femoral condyle prosthesis and the high polymer tibia gasket are matched, the matched has good wear resistance, small abrasion loss, no metal ion precipitation and good development prospect, but the ceramic femoral condyle prosthesis is easy to crack due to the inherent fragility of ceramic, and is still in a laboratory research stage at present and has no clinical application.
Therefore, the friction between the femoral condyle prosthesis and the tibial gasket is reduced, the abrasion loss of the tibial gasket is reduced, the service life of the tibial gasket is prolonged, and the femoral condyle prosthesis is a necessary requirement for improving the life quality of a patient.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide the knee joint prosthesis to achieve the purposes of reducing the abrasion of the femoral condyle prosthesis and the liner, reducing the ceramic cracking risk, reducing the release of metal ions and prolonging the service life of the knee joint prosthesis.
In order to solve the technical problems, the invention adopts the following technical scheme:
The knee joint prosthesis comprises a femoral condyle prosthesis, a liner and a tibial plateau support, wherein the liner is arranged on the tibial plateau support, ceramic plates used for reducing abrasion of the femoral condyle prosthesis and the liner are arranged on the femoral condyle prosthesis, the ceramic plates are a group of ceramic plates which are distributed in a scattered manner, the ceramic plates are connected with the femoral condyle prosthesis through welding, and the convex curved surface of the ceramic plates is contacted with the upper surface of the liner to form a friction pair.
Preferably, an intermediate is arranged between the ceramic plates, and the intermediate is a high-molecular polymer. Grooves or protrusions are formed in the outer peripheral surface of the connecting portion of the ceramic plate and the intermediate body.
Preferably, the convex curved surface of the ceramic plate protrudes from the outer surface of the femoral condyle prosthesis or is in the same curved surface as the outer surface of the femoral condyle prosthesis.
Preferably, the curvature of the convex curved surface of the ceramic plate is consistent with the curvature of the outer surface of the femoral condyle prosthesis.
Preferably, the femoral condyle prosthesis is provided with two condyle outer surfaces, and ceramic plates which are distributed on the two condyle outer surfaces are respectively arranged on the two condyle outer surfaces.
Preferably, the ceramic sheet is cylindrical and/or polygonal or irregularly shaped.
Preferably, the liner is a high molecular polymer or a compound or surface modified, the femoral condyle prosthesis is titanium or alloy or tantalum or alloy thereof or medical stainless steel or cobalt-chromium alloy, and the ceramic plate is a biological ceramic.
Preferably, the inner surface of the femoral condyle prosthesis and the part of the outer surface of the lower part of the tibial plateau support, which is contacted with the host bone, are provided with a group of holes which are suitable for the growth of human tissues, are convenient for biological connection and enhance the clinical long-term connection effect.
Preferably, the upper surface of the pad is provided with a set of pockets for storing bodily fluids.
Compared with the prior art, the invention has the following advantages:
according to the invention, the femoral condyle prosthesis is provided with the plurality of ceramic plates, so that the traditional metal femoral condyle prosthesis is replaced, the friction between metal and the high polymer liner is converted into the friction between ceramic and the high polymer liner, and meanwhile, gaps are reserved between the ceramic plates to accommodate lubricating liquid, thereby reducing the friction coefficient between the femoral condyle prosthesis and the tibial liner, reducing the abrasion loss and reducing the precipitation of metal ions; meanwhile, the fracture risk of the ceramic femoral condyle type prosthesis can be reduced; the quality of the knee joint is reduced, so that the movement of a patient is lighter; the high molecular polymer between the ceramic plates has certain impact resistance and noise reduction effect.
Detailed Description
The following description of the embodiments of the present invention refers to the accompanying drawings, which illustrate in further detail.
The knee joint prosthesis comprises a femoral condyle prosthesis, a tibial liner and a tibial platform support, wherein the tibial liner is arranged on the tibial platform support, the outer surface of the femoral condyle prosthesis corresponds to the upper surface of the tibial liner, ceramic plates for reducing friction between the outer surface of the femoral condyle prosthesis and the upper surface of the tibial liner are arranged on the outer surface of the femoral condyle prosthesis or the upper surface of the tibial liner, the ceramic plates are in a group, and the ceramic plates in a group are distributed in a discrete mode, and can be particularly distributed at uniform or non-uniform intervals. The non-uniform spacing arrangement can increase the contact area and thereby reduce the contact stress.
Wherein, the inner surface of the femoral condyle prosthesis and the part of the outer surface of the lower part of the tibial plateau support, which is contacted with the host bone, are provided with a group of holes which are suitable for the growth of human tissues, are convenient for biological connection and enhance the clinical long-term connection effect, and the group of holes are a group of micropores; the micropores can enable bone tissues to grow into the micropores, strengthen the connection between joints and host bones of a human body, improve the fixing reliability of the prosthesis in the human body and ensure the use effect.
The invention is illustrated below by means of specific examples, in particular as follows:
As shown in fig. 1 to 3, the knee joint prosthesis comprises a femoral condyle prosthesis 1, a ceramic plate II 202, a tibial liner 3 and a tibial platform support 4, wherein the liner is a high polymer or a compound or surface modified, the femoral condyle prosthesis is titanium or alloy thereof or tantalum or alloy thereof or medical stainless steel or cobalt-chromium alloy, and the ceramic plate is biological ceramic.
The ceramic plate II is a quadrangular prism body or a hexagonal prism body or a cylinder, one surface of the ceramic plate II is connected with the outer surface of the femoral condyle prosthesis through welding, the femoral condyle prosthesis 1 is prepared by adopting a powder metallurgy sintering method, the material of the femoral condyle prosthesis 1 is preferably medical titanium alloy, two end surfaces of the ceramic plate II are arc-shaped, the ceramic plate is positioned on the same arc surface after laser welding, the material of the ceramic plate II is preferably alumina ceramic, and the convex curved surface of the ceramic plate contacts with the upper surface of the liner to form a friction pair.
The ceramic plates are in the shape of cylinders and/or polygonal columns, and a group of ceramic plates are arranged at non-uniform intervals, so that the contact area can be increased.
Both end surfaces of the ceramic plate are arc-shaped; specifically, the ceramic plate is provided with a convex curved surface and a concave curved surface; the convex curved surface of the ceramic plate protrudes out of the outer surface of the femoral condyle prosthesis or is in the same curved surface with the outer surface of the femoral condyle prosthesis. The curvature of the convex curved surface of the ceramic plate is consistent with the curvature of the outer surface of the femoral condyle prosthesis. The femoral condyle prosthesis is provided with two condyle outer surfaces, and ceramic plates which are distributed and arranged on the two condyle outer surfaces. The stress is uniform, stable and reliable.
An intermediate is arranged between the ceramic plates, the intermediate is a high-molecular polymer, and the surface of the high-molecular polymer is lower than the convex curved surface of the ceramic plates. Grooves or protrusions are arranged on the peripheral surface of the connecting part of the ceramic piece and the intermediate body. Preferably, the grooves on the ceramic plates are spiral grooves, high-molecular polymers are arranged in the grooves, and the arrangement of the grooves increases the extraction force and binding force of the ceramic plates, so that the ceramic plates are fixed more firmly.
A certain gap is arranged between the adjacent ceramic plates, and the gap can be used for storing human body fluid; the upper surface of the pad is provided with a group of pits for storing human body fluid, and the group of pits are a group of micro pits for storing human body fluid; and the contact surface of the ceramic plate and the tibia pad is lubricated, so that friction between the ceramic plate and the tibia pad is reduced.
Or the outer surface of the femoral condyle prosthesis is provided with a groove which is used for accommodating the supporting body, a group of ceramic plates are distributed on the supporting body, and the convex curved surfaces of the ceramic plates are contacted with the upper surface of the liner to form a friction pair. Wherein the support is a high molecular polymer. The contact surface of the ceramic plate and the femur prosthesis does not need finish machining, so that the machining process is reduced, the cost is reduced, and the ceramic plate has certain impact resistance and noise reduction effects. Grooves or protrusions are formed on the outer peripheral surface of the portion, connected with the supporting body, of the ceramic plate. Preferably, the grooves on the ceramic sheet are spiral grooves. The supporting body is made of high-molecular polymer, the ceramic plate is inlaid in the high-molecular polymer, the high-molecular polymer is arranged in the groove, and the pull-out force and the binding force of the ceramic plate are increased by the arrangement of the groove, so that the ceramic plate is fixed more firmly.
As shown in fig. 4 to 6, the knee joint prosthesis comprises a femoral condyle prosthesis, a ceramic plate i 201, a tibial liner and a tibial plateau support, wherein the femoral condyle prosthesis 1 is of a metal structure, so that the femoral condyle prosthesis is convenient to be connected with a human skeleton. The ceramic plate I is a quadrangular prism or a hexagonal prism or a cylinder, the tibia pad 3 has the function similar to a meniscus structure, the upper part is in a half-moon arc shape, the lower part is in a platform shape, the upper part is in contact with the femur condyle prosthesis 1, the lower part is fixed with the tibia platform support 4, and the ceramic plate I is inlaid on a half-moon curved surface with a certain radian which is downwards concave in the tibia pad 3.
The ceramic plate I protrudes to a certain height, the preparation method of the tibia gasket 3 comprises injection molding or 3D additive manufacturing technology, and the preparation method of the femur condyle prosthesis and the tibia platform bracket can adopt powder metallurgy sintering method, plasma spraying method or three-dimensional printing rapid prototyping technology.
The tibia pad and the supporting body are made of high molecular polymer, preferably ultra-high molecular weight polyethylene, the ceramic plate I is made of biological ceramic, preferably alumina ceramic, and the ceramic plate I and the tibia pad are connected by filling polyethylene materials.
Grooves or protrusions are formed on the outer peripheral surface of the connecting part of the ceramic plate and the tibia pad; preferably, the groove is a spiral groove, the groove is arranged in the tibia pad, the extraction force and the binding force of the ceramic plate are increased, and the ceramic plate is reliably fixed.
The outer surface of the femoral condyle prosthesis is provided with a group of pits, and the group of pits are a group of micro pits and are used for storing body fluid of a human body, lubricating the contact surface of the femoral condyle prosthesis and the ceramic plate, reducing friction of the femoral condyle prosthesis and the ceramic plate and reducing abrasion loss. A certain gap is arranged between the adjacent ceramic plates, and the gap can be used for storing human body fluid, lubricating the contact surface of the ceramic plates and the tibia pad and reducing friction between the ceramic plates and the tibia pad. The two structures act together, and the abrasion loss of the ceramic plate and the femoral condyle prosthesis is very small.
The tibia pad or the femur condyle prosthesis in the knee joint prosthesis is provided with a plurality of ceramic plates, so that the frictional wear between metal and high polymer materials is converted into the frictional wear between ceramics and high polymer, and the abrasion of the traditional femur condyle prosthesis and tibia pad is reduced, thereby avoiding metal ion precipitation caused by the friction between metal and high polymer; the ceramic plates are dispersed and arranged, so that the ceramic plates are not easy to crack, the brittle performance of the ceramic plates is overcome, the quality of the knee joint is lightened, and the movement of a patient is lighter.
While the invention has been described above with reference to the accompanying drawings, it will be apparent that the invention is not limited to the above embodiments, but is capable of being modified or applied to other applications without any modification, as long as the inventive concept and technical scheme are adopted.